Aside from pregnancy, travel warnings, and frequent fumigation in areas to kill virus-spreading mosquitoes, a program in El Salvador is also turning to another cost-effective technique to prevent the spread of other mosquito-born diseases like dengue: fish.
El Salvador is one of the countries that reported a spike in Zika cases. When the links between the Zika virus and babies born with microcephaly in Brazil and other Latin American countries became a concern, they were one of the nations to issue warnings to women to delay pregnancy until 2018 as a precaution.
The sambo fish (sometimes called zambo fish) are being distributed by volunteers in restaurants, schools, and other areas that keep open barrels and other structures used for collecting water where mosquitoes are likely to lay their eggs. The fish eat the larvae of the mosquitoes and stop them from developing into breeding adults that spread the virus.
A volunteer group in La Libertad in El Salvador has been distributing fish in San Diego village as a control project to prevent the breeding of mosquitoes that transmit Zika as well as dengue and chikungunya.
According to Marielos Sosa, one of the Health Workers on the project, the fish had been used in the village from 2012 to 2015 and they had zero cases of dengue during that period. The community also had no cases of chikungunya and so far no cases of Zika either.
Sosa credits the fish distribution program for keeping the community of San Diego village virus-free despite that fact that 5,000 cases of Zika were reported in El Salvador between 2015 and 2016.
On Wednesday, Eduardo Espinosa, the country's vice minister of health, acknowledged that the biological effort of such programs have been used by the government as an additional measure to curb the spread of the disease.
“The Salvadoran government has put in place measures for vector control, including water treatment, the use of window screens, and fogging and area sprays. Biological control mechanisms include mosquito-eating fish in home water tanks. These have been successful, building on the premise that the central effort should be to mobilize the whole society against the Zika-carrying mosquito,” he wrote in a letter.
It is to be noted that the sambo fish are not placed in natural waterways where they could impact the natural eco-balance. They are placed in open barrels and water tanks which are common in El Salvador and are prime breeding grounds for mosquitoes.
